Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B39/00—Evaporators; Condensers
  • F25B39/02—Evaporators
  • F25B39/026—Evaporators specially adapted for sorption type systems
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B17/00—Sorption machines, plants or systems, operating intermittently, e.g. absorption or adsorption type
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25C—PRODUCING, WORKING OR HANDLING ICE
  • F25C1/00—Producing ice
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
  • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
  • F25B2400/00—General features or devices for refrigeration machines, plants or systems, combined heating and refrigeration systems or heat-pump systems, i.e. not limited to a particular subgroup of F25B
  • F25B2400/24—Storage receiver heat
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
  • Y02A30/00—Adapting or protecting infrastructure or their operation
  • Y02A30/27—Relating to heating, ventilation or air conditioning [HVAC] technologies
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
  • Y02B30/00—Energy efficient heating, ventilation or air conditioning [HVAC]
  • Y02B30/62—Absorption based systems

Definitions

• the invention relates to an installation and a method for producing cold by a reversible sorption system, in particular for freezing various products or for producing fresh water or ice cubes.
• a reversible sorption can be an absorption of a gas by a liquid, an adsorption of a gas on a solid, or a reaction between a gas and a solid.
• a reversible sorption between a sorbent S and a gas G is exothermic in the direction of the synthesis S + G -> SG, and endothermic in the direction of the decomposition SG - S + G. In a change of liquid phase / gas of G , the condensation is exothermic and evaporation is endothermic.
• P and T being respectively the pressure and the temperature
• ⁇ ⁇ and ⁇ S - being - respectively - -1 'enthalpy - and - ⁇ l -' entropy of the phenomenon (decomposition, synthesis, evaporation, condensation) brought into play
• R being the constant of the ideal gases.
• the endothermic stage can be used in an installation of this type for freezing various products (in particular water for obtaining ice cubes) or for the production of cold water.
• EP0810410 describes a device comprising a reactor and an evaporator / condenser connected by a pipe fitted with a valve.
• the reactor is the site of a thermochemical reaction or a solid-gas adsorption. It comprises means for heating the solid which it contains and means for removing the heat from the exothermic synthesis reaction, these means being constituted either by a heat exchanger, either by increasing the thermal mass of the reactor.
• the reactor is arranged so that, with its contents, it has a sufficient thermal mass to absorb the heat produced during the exothermic reaction.
• the method of managing this device consists in putting the evaporator / condenser in communication with the reactor when the evaporator / condenser is filled with the working gas in liquid form, which has the effect of cooling the evaporator / condenser by evaporation. , then to
• the reactor traverses a thermal amplitude between the regeneration temperature and the relatively large ambient temperature, which induces a low coefficient of performance.
• the object of the present invention is to provide a device capable of producing an igorific volume. very high, for example of the order of 200 k / m 3 , at a relatively low useful temperature T ⁇ and with greatly reduced cycle times and more attractive performance.
• useful temperature is meant the temperature
• Freezing of products (freezing of water to produce ice or freezing of other products) or the temperature at which it is desired to lower and maintain products without freezing them (for example to obtain fresh water).
• An installation according to the present invention for producing cold at temperature T 0 comprises a reactor
• (1) which is the seat of a reversible sorption P H ⁇ involving a gas G and a sorbent S, a device (2) seat a reversible phenomenon P B ⁇ which involves the gas G, means for putting the device (2) in communication with the reactor (1) and means for isolating the reactor (1) from the device (2), the equilibrium curve of the reversible phenomenon in (2) being located in a lower temperature domain than that of the equilibrium curve of the reversible sorption in (1) in the Clapeyron diagram.
• the installation is characterized in that the device (2) contains, in addition to the gas G, a material with change of
• the phase change material can be chosen, for example, from paraffins such as n-alkanes having from 10 to 20 carbon atoms, eutectic mixtures and eutectic solutions.
• the reversible sorption in the reactor (1) can be any suitable reversible sorption in the reactor (1).
• the reversible phenomenon in the device (2) can be chosen from the reversible chemical reactions between —25— gas G and a -solid, - adsorptions of gas G on _un. solid, absorption of gas G by a liquid, changes of liquid phase / gas of gas G. Changes of liquid phase / gas are preferred, because they make it possible to produce cold with greater speed than with sorptions,
• gas G As an example of gas G, mention may be made of ammonia (NH 3 ) and its derivatives, hydrogen (H 2 ), carbon dioxide (C0 2 ), water (H 2 0), sulphide hydrogen (H 2 S), methane and other natural gases.
• NH 3 ammonia
• C0 2 carbon dioxide
• H 2 0 water
• H 2 S sulphide hydrogen
• methane methane and other natural gases.
• the exothermic synthesis step in the reactor (1) which is concomitant with the dissociation step generating the cold in the device (2), is favored if the content of the reactor (1) is kept at a temperature below its 5 equilibrium temperature at the pressure prevailing in the reactor (1). It is therefore preferable to neutralize the action of the heat produced as the synthesis takes place in the reactor (1) in order to maintain the greatest possible difference between the actual temperature of the reactor.
• ammoniacates for example chlorides, bromides, iodides or sulfates
• the production of cold takes place at the level of the device (2). If the cold produced is intended for the production of ice cubes or cold water, the device (2) is in direct thermal contact
• the tank (3) can be a coil in which circulates
• the tank (3) has the appropriate shape to contain and freeze the products.
• the liquid / solid phase change material is
• T s which is some degrees lower than the useful temperature Tu, that is to say the temperature of the product to be frozen or cooled, for example below 0 ° C. when the goal is to make ice cubes, or less than the
• the subject of the invention is also a method for producing cold by a thermochemical system comprising at least two reversible phenomena using a gas G, in which the cold is produced during the step of dissociation of the reversible phenomenon P BT whose equilibrium curve in the Clapeyron diagram is located in the domain of low temperatures, and the system is regenerated during the step of dissociation of the reversible phenomenon P H ⁇ whose equilibrium curve in the Clapeyron diagram lies in the domain of high temperatures. It is characterized in that the stage of production of cold is extended beyond the end of the stage of dissociation of the
• phase change material has a double effect. On the one hand, it decreases the control temperature.
• the method according to the invention for producing cold is implemented using an installation as described above. It comprises the following steps: a) place the installation in an initial state in -25 — which-the .. reactor .... (1) .... and. the device .. (, 2) ..
• (2) contains the gas G in the liquid state and the material M in the liquid state
• (1) contains the sorbent S in a gas-poor state
• the content of (1) and the content of (2) are at room temperature T ⁇
• the reservoir (3) contains the products to be frozen or cooled; b) placing the reactor (1) and the device (2) in communication for the endothermic release of the gas G in (2) and the exothermic sorption of the gas G on the sorbent S in (1), with production of cold in the device (2)
• step b) isolating the reactor (1) from the device (2) to prolong the production of cold in (2) by melting the material M which releases the cold accumulated in the form of latent heat, and bring energy
• the different phases of the process are triggered by means within the reach of those skilled in the art, such as timers, for example by means of a clock or a timer.
• the duration of the different phases depends on the goal sought [quantity of ice cubes desired per unit of time,
• FIG. 1 represents a diagram of an installation according to the invention.
• the installation includes a reactor
• the device (2) is advantageously an evaporator / condenser (hereinafter referred to as an evaporator).
• the evaporator (2) is in direct thermal contact with a tank (3) integrated in the wall of
• the reactor (1) is provided with heating means (5) and heat extraction means (6).
• FIGS. 2 to 8 show the position of the installation in the Clapeyron diagram, different
• Ln (P) on the ordinate designates the logarithm of the pressure P
• T on the abscissa axis designates the temperature.
• P EV designates the pressure in the evaporator
• P RE designates the pressure in the reactor
• AM designates the temperature
• T EV and T RE denote the temperature at a given instant respectively in the evaporator and in the reactor
• T E Q denotes the equilibrium temperature in the reactor for a given pressure
• T REG denotes the temperature of regeneration in the reactor (1).
• VO means that the valve (4) is open, and VF means that the valve (4) is closed.
• a complete cycle of production of cold and regeneration of the installation is described below, for an installation in which the reactor (1) is the seat of a reversible sorption between a solid S and a gas G.
• the gas G is alternately evaporated or condensed.
• the installation is placed in an initial state: the evaporator and the reactor are at ambient temperature T AM and at their respective equilibrium pressure at this temperature P EV and P RE , P E v being greater than P RE .
• the evaporator (2) contains the gas G in the liquid state.
• the reactor (1) contains the sorbent S in the gas-poor state.
• the valve (4) is closed.
• the reservoir (3) contains water in the liquid state.
• the Clapeyron diagram corresponding to this state is shown in Figure 2.
• the reactor (1) and the evaporator (2) are placed in communication by opening the valve (4).
• the evaporation of gas G in (2) causes a sudden drop in the temperature T EV in (2) with cooling of the water, possibly until the water freezes to form ice cubes in the tank (3) , then solidification of the mat-é-riau -—M — dont- - la. ... temperature. ..solidification : .. _ . is below the ice formation temperature.
• the gas G released by evaporation in (2) is absorbed by the sorbent contained in (1) during the exothermic synthesis, which causes a rise in temperature at T RE of the reactor due to the exothermic nature of this absorption.
• the valve (4) remains open and the means (6) are activated to remove the heat produced 5 in the reactor (1) which cannot be absorbed by the thermal mass of said reactor in order to maintain the sorbent S under the synthesis conditions (T RE ⁇ T EQ ) when the thermal mass of the reactor proves to be insufficient to absorb all of the heat of reaction.
• This phase is useless if
• the valve (4) is closed to isolate the reactor (1) from the evaporator (2).
• the reactor (1) thus isolated is then heated by the heating means (5) and it is then placed on its thermodynamic equilibrium. This heating allows the reactor to move along
• Phase 4 is thus a transient phase for heating the reactor and continuing the production of cold by melting the phase change material.
• the Clapeyron diagram corresponding to this phase is shown in Figure 5.
• the reactor (1) is placed in communication with the evaporator (2) by opening the valve (4) and the reactor (1) is kept heated by the heating means (5 ).
• the communication of the placed reactor under high pressure regeneration conditions with one evaporator maintained at low pressure by the phase change material allows rapid desorption of the gas from the reactor.
• the evaporator, receiving hot gases from the reactor, then acts as a condenser.
• This phase is a rapid regeneration phase of the reactor and detachment of the ice cubes.
• the Clapeyron diagram corresponding to this phase is shown in Figure 6.
• Phase 6 begins when the change material _25 — phase- has - completely melted.
• the pressure in (2) increases, which has the effect of reducing the temperature difference of the reactor with respect to the thermodynamic equilibrium of the reaction and therefore of reducing the quantity of gas desorbed. Heating the reactor (1) by the means (5) then allows the
• Phase 7 begins as soon as regeneration is complete.
• the valve (4) is closed.
• the isolated reactor (1) is cooled if
• the reactor (1) wants to immediately start a new production cycle, or the reactor (1) is allowed to cool itself if the cycle time does not matter, which causes a drop in temperature and pressure.
• the device is thus puts in the initial conditions of the storage phase of cold production at the start of the operating cycle.
• the Clapeyron diagram corresponding to this step is shown in FIG. 8.
• the installation and the method according to the invention are particularly advantageous when the device (2) is an evaporator / condenser (hereinafter referred to as an evaporator).
• the evaporator has a structure as shown in FIGS. 9
• Figure 9 shows a cross-sectional view
• Figure 10 shows a longitudinal sectional view
• one evaporator consists of a cylinder (8) which is closed at both ends and which has at its upper part a
• the outer wall of the evaporator (8) is made of a material having a high thermal diffusivity
• the ice cube tray 7 is provided with multiple transverse partitions, placed so as to obtain the desired shape for the ice cubes.
• the overall shape of the ice cube tray has a toroidal half-moon geometry which allows easy demolding of the ice cubes formed.
• phase change material M placed between the walls of the hollow fins maintains the temperature of the evaporator at a value which makes it possible to prolong the phase of ice production during the transient heating phase for the regeneration of the reactor isolated from the evaporator .
• the particular configuration of the tube (10) and its position in the enclosure of the evaporator are such that the hot gases, coming from the reactor during the phase 5 of communication between the high pressure reactor and the evaporator maintained at low pressure by the phase change material, first strike the wall of the ice cube tray, which facilitates detachment of the ice cubes.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Mechanical Engineering (AREA)
• Thermal Sciences (AREA)
• General Engineering & Computer Science (AREA)
• Sorption Type Refrigeration Machines (AREA)
• Solid-Sorbent Or Filter-Aiding Compositions (AREA)
• Drying Of Gases (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=30011444

Family Applications (1)

Country Status (10)

Families Citing this family (5)

Family Cites Families (4)

• 2002
  • 2002-07-24 FR FR0209390A patent/FR2842891B1/fr not_active Expired - Fee Related
• 2003
  • 2003-07-11 EP EP03771134A patent/EP1529185B1/de not_active Expired - Lifetime
  • 2003-07-11 PT PT03771134T patent/PT1529185E/pt unknown
  • 2003-07-11 ES ES03771134T patent/ES2280811T3/es not_active Expired - Lifetime
  • 2003-07-11 US US10/491,196 patent/US7624584B2/en not_active Expired - Fee Related
  • 2003-07-11 JP JP2004523847A patent/JP4294587B2/ja not_active Expired - Fee Related
  • 2003-07-11 AU AU2003264715A patent/AU2003264715A1/en not_active Abandoned
  • 2003-07-11 AT AT03771134T patent/ATE354772T1/de not_active IP Right Cessation
  • 2003-07-11 DE DE60311996T patent/DE60311996T2/de not_active Expired - Lifetime
  • 2003-07-11 WO PCT/FR2003/002217 patent/WO2004011858A2/fr not_active Ceased

Non-Patent Citations (1)

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